3D-printed customised titanium mesh and bone ring technique for bone augmentation of combined bone defects in the aesthetic zone.

PURPOSE: Complex bone defects with a horizontal and vertical combined deficiency pose a clinical challenge in implant dentistry. This study reports the case of a young female patient who presented with a perforating bone defect in the aesthetic zone. MATERIALS AND METHODS: Based on prosthetically guided bone regeneration, virtual 3D bone augmentation was planned. A 3D printed customised titanium mesh and the autogenous bone ring technique were then utilised simultaneously to achieve a customised bone contour. After 6 months, the titanium mesh was removed and connective tissue grafting was performed. Finally, implants were placed and the provisional and definitive prostheses were delivered following a digital approach. Vertical and horizontal bone gain, new bone density, pseudo-periosteum type and marginal bone loss were measured. Planned bone volume, regenerated bone volume and regeneration rate were analysed. RESULTS: Staged tooth shortening led to a coronal increase in keratinised mucosa. The customised titanium mesh and bone ring technique yielded 14.27 mm vertical bone gain and 12.9 mm horizontal bone gain in the perforating area. When the titanium mesh was removed, the reopening surgery showed a Type 1 pseudo-periosteum (none or < 1 mm), and CBCT scans revealed a new bone density of ~550 HU. With a planned bone volume of 1063.55 mm3, the regenerated bone volume was 969.29 mm3, indicating a regeneration rate of 91.14%. The 1-year follow-up after definitive restoration revealed no complications except for 0.55 to 0.60 mm marginal bone loss. CONCLUSION: Combined application of customised titanium mesh and an autogenous bone ring block shows promising potential to achieve prosthetically guided bone regeneration for complex bone defects in the aesthetic zone.

Efficacy of bone ring grafts for the reconstruction of alveolar ridge deficiencies: a systematic review. Part II: animal trials.

Background: Bone ring (BR) grafts have been introduced to reconstruct alveolar ridge defects with simultaneous implant placement, but their clinical effectiveness remains undetermined. The aim of the current systematic review was to critically appraise evidence from animal studies regarding the effectiveness of BR grafts in alveolar ridge reconstruction and their variations under different surgical protocols. Methods: Electronic retrieval of six databases (MEDLINE, Embase, Cochrane Library, ScienceDirect, Web of Science, and Scopus) and citation search until 11 October 2023, for animal studies on bone augmentation employing BR grafts. The outcome variables were total bone area (BA), bone volume (BV), bone-implant contact (BIC), and histology. The protocol was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and prospectively registered with PROSPERO (CRD42023453949). Results: Ten studies were included in the qualitative analysis according to the screening criteria. Two studies demonstrated favorable bone remodeling and osseointegration of the BR with both the implant and pristine bone. A comparative study between autogenous BRs and allogenic BRs reported a higher percentage of BA and BIC at 4 months of healing, but conflicting data were observed at 8 months. Another study indicated a significant advantage of autogenous BRs over bovine and biphasic ceramic BRs in terms of BA and BIC after 5 weeks. Three studies found that using collagen membranes did not significantly affect BA, BV, or BIC when used simultaneously with autogenous BRs during implant placement. Two studies evaluated one-stage and two-stage implant placement in conjunction with BR grafts, revealing similar levels of BA, BV, and BIC except for differences in total treatment time. Furthermore, one study found that the use of mucogingival junction incision and split-thickness flap significantly reduced the incidence of wound dehiscence compared with conventional incision and flap. Conclusions: Vertical bone augmentation surgery utilizing BR grafts with one-stage implant placement yielded histological and histomorphometric outcomes comparable to those achieved with two-stage implant placement or the additional application of collagen membrane.

Vertical alveolar bone augmentation of atrophied posterior mandibular regions with simultaneous dental implant placement using allogeneic bone rings vs autogenous bone rings: a randomized controlled clinical trial.

OBJECTIVE: Ideal implant placement in atrophied posterior mandibular regions is challenging due to surgical difficulties and anatomical limitations. This study aimed to evaluate the use of allogeneic bone rings for vertical augmentation of atrophied posterior mandibular regions with simultaneous implants compared to autogenous bone rings, while avoiding donor site morbidity. METHOD AND MATERIALS: A total of 24 vertically atrophied posterior mandibular segments (in 14 patients) were equally randomized into a study group in which mineralized freeze-dried allogeneic bone rings were used, and a control group in which autogenous bone rings with prepared implant osteotomies were harvested from the chin and used. All augmentation sites were prepared before inserting the bone rings. Implants were simultaneously inserted, fixing the bone rings into the native bone. All patients were clinically assessed after 1 week, 2 weeks, and 1 month. Crestal bone level was radiographically assessed after 1 week, 6 months, and 3 months of prosthetic loading. RESULTS: None of the 24 bone rings showed signs of implant or graft failure. There was no significant difference in the crestal bone level between the groups. CONCLUSION: Allogeneic bone rings can be a viable alternative to autogenous bone rings in augmenting the posterior aspect of the mandible, mitigating the concerns associated with donor site complications.

Autogenous bone ring augmentation around single tooth implantation in the esthetic zone: A retrospective case series study with 2-3 years of follow-up.

Background: /purpose: Bone ring technique (BRT) is an effective method to reconstruct alveolar bone defects with simultaneous implant placement. This study aimed to evaluate the efficacy of the BRT in single maxillary anterior tooth implantation and its esthetic outcomes over 2-3 years of follow-up. Materials and methods: Fifteen patients with single maxillary incisor loss received autogenous BRT with simultaneous implant placement. The vertical/horizontal bone gain, remaining vertical bone height (RVBH), remaining buccal bone width (RBBW), and vertical/horizontal bone resorption around implant over 2-3 years of follow-up were measured by using cone-beam computed tomography. Esthetic results including white esthetic score (WES), pink esthetic score (PES), and papilla index (PI) were evaluated by clinical recorded photographs. Results: All implants showed evidence of osseointegration, and the mean vertical and horizontal bone gain of 14 sites was 5.55 ± 0.87 mm and 4.73 ± 0.70 mm, respectively. During 2-3 years of follow-up, all mean values of RBBW were more than 2 mm. Main vertical bone loss appeared within 4 months after surgery and the RVBH value decreased as the follow-up duration continued. Maximum buccal bone thickness resorption mostly appeared in the middle level of the implant during the primary two follow-up periods (P < 0.05). Esthetic results showed that the mean WES/PES was higher than 17, and more than half cases demonstrated relatively high PI (3 points) throughout the follow-up. Conclusion: BRT could achieve excellent bone augmentation effect and can offer predictable esthetic outcomes for single tooth implant restoration in the esthetic zone.

Implant Placement Using the Bone Ring Technique With and Without Membrane Placement: A Preclinical 12-Month Study in Dogs.

The bone ring technique is applied for vertical augmentation, in which the dental implant and autogenous block bone graft are simultaneously inserted. We investigated the healing of bone around implants placed simultaneously using the bone ring technique with and without membrane placement after a 12-month healing period. Vertical bone defects were created on both sides of the mandible of Beagle dogs. Implants were inserted into the defects through bone rings and fixed with membrane screws as healing caps. The augmented sites on one side of the mandible were covered with a collagen membrane. Samples were harvested 12 months after implantation and assessed histologically and by microcomputed tomography analysis. All implants remained throughout the healing period; however, except for 1 implant, they showed lost caps and/or exposure to the oral cavity. The implants had contact with newly formed bone despite frequent bone resorption. The surrounding bone appeared mature. The medians of bone volume and percentages of total bone area and bone-to-implant contact within the bone ring were slightly higher in the group with membrane placement than in that without membrane placement. Nevertheless, none of the evaluated parameters were significantly affected by the membrane placement. In the present model, soft tissue complication was frequent, and the membrane application did not reveal the effect at 12 months after implant placement using the bone ring technique. Sustained osseointegration and maturation of surrounding bone were observed in both groups after a 12-month healing period.

Bone allograft block using demineralized freeze-dried bone ring technique in Indian patients.

Our study aimed to evaluate the effectiveness of the bone ring technique for ridge augmentation using Demineralized Freeze - Dried Bone Allograft block in Siebert's class II/class III defects along with simultaneous implant placement. A total of 15 partially edentulous patients (16 surgical sites) with Siebert's class II and/or class III defects in the anterior region of both jaws requiring ridge augmentation along with implant placement were selected. Starting from the first stage, surgery (Ridge augmentation+ implant placement) was done in the first month. Then, with continuous follow-ups and radiographic assessment, after 6 months of 2nd stage surgery was done, the implant was loaded with the final restoration. Significant results were revealed with all the parameters other than keratinized gingival and peri-implant mucosa thickness. With the mean bone resorption of 1.22 mm and 1.17 mm at the mesial and distal site at a 6-month interval, the success rate of the bone ring technique was 93.75%. The allograft bone ring technique showed a favorable outcome for the reconstruction of large vertical defects.

Impact of simultaneous placement of implant and block bone graft substitute: an in vivo peri-implant defect model.

BACKGROUND: Insufficient bone volume around an implant is a common obstacle when dental implant treatment is considered. Limited vertical or horizontal bone dimensions may lead to exposed implant threads following placement or a gap between the bone and implant. This is often addressed by bone augmentation procedures prior to or at the time of implant placement. This study evaluated bone healing when a synthetic TiO2 block scaffold was placed in circumferential peri-implant defects with buccal fenestrations. METHODS: The mandibular premolars were extracted and the alveolar bone left to heal for 4 weeks prior to implant placement in six minipigs. Two cylindrical defects were created in each hemi-mandible and were subsequent to implant placement allocated to treatment with either TiO2 scaffold or sham in a split mouth design. After 12 weeks of healing time, the samples were harvested. Microcomputed tomography (MicroCT) was used to investigate defect fill and integrity of the block scaffold. Distances from implant to bone in vertical and horizontal directions, percentage of bone to implant contact and defect fill were analysed by histology. RESULTS: MicroCT analysis demonstrated no differences between the groups for defect fill. Three of twelve scaffolds were partly fractured. At the buccal sites, histomorphometric analysis demonstrated higher bone fraction, higher percentage bone to implant contact and shorter distance from implant top to bone 0.5 mm lateral to implant surface in sham group as compared to the TiO2 group. CONCLUSIONS: This study demonstrated less bone formation with the use of TiO2 scaffold block in combination with implant placement in cylindrical defects with buccal bone fenestrations, as compared to sham sites.

Animal models of vertical bone augmentation (Review).

Vertical bone augmentation is an important challenge in dental implantology. Existing vertical bone augmentation techniques, along with bone grafting materials, have achieved certain clinical progress but continue to have numerous limitations. In order to evaluate the possibility of using biomaterials to develop bone substitutes, medical devices and/or new bone grafting techniques for vertical bone augmentation, it is essential to establish clinically relevant animal models to investigate their biocompatibility, mechanical properties, applicability and safety. The present review discusses recent animal experiments related to vertical bone augmentation. In addition, surgical protocols for establishing relevant preclinical models with various animal species were reviewed. The present study aims to provide guidance for selecting experimental animal models of vertical bone augmentation.

Evaluation of Resorption and Osseointegration of Autogenous Bone Ring Grafting in Vertical Bone Defect With Simultaneous Implant Placement in Dogs.

The aim of this research was to evaluate the resorption and osseointegration of an autogenous bone ring, which was grafted in a local vertical alveolar defect with simultaneous implant placement. Six Beagle dogs were enrolled in the study; their 4 nonadjacent mandibular premolars were extracted, and the buccal plate was removed to create bone defects in 2 of the 4 sites. Three months after extraction, Straumann implants (Ø 3.3 mm, length of 8 mm) were placed in the bone defect sites with simultaneous autogenous bone ring grafting and in the conventional extraction sites. After a 3-month healing period and a 3-month loading period, the animals were euthanized. The harvested samples were analyzed using micro-computed tomography (CT) scanning and histological analysis. From the micro-CT measurements, the average vertical bone resorption of the bone ring was 0.23 ± 0.03 mm, which was not significantly different from that around the conventional implant, 0.24 ± 0.12 mm (P > .05). The ratio of the bone volume to the total volume of the bone ring group was 91.11 ± 0.02, which was higher than that of the control group, 88.38 ± 2.34 (P < .05). From the hard tissue section, the bone rings developed fine osseointegration with the implants and the base alveolar bone. The results suggest autogenous bone ring grafting with simultaneous implant placement can survive in a local vertical bone defect with little bone resorption and good osseointegration in dogs with strict management. A bone ring graft must be compared with guided bone regeneration, and a larger and longer observation must be confirmed in clinical patients.

Intra-sinusal bone ring concomitant with Le Fort 1 osteotomy: description of a technique.

AIM: To present a technical note on intra-sinusal bone ring concomitant with Le Fort 1 osteotomy. MATERIAL AND METHOD: A 57-year-old man was referred to our Department for full-mouth rehabilitation. Oral examination identified: uncompensated multiple tooth loss and a class 3 skeletal malocclusion. The treatment plan consisted in a Le Fort 1 osteotomy and short-arch dental implant rehabilitation. Intra-sinusal bone ring technique associated with Le Fort 1 osteotomy were carried out under general anaesthesia. RESULT: High primary retention was clinically observed of both the implant and the bone graft. Radiographic follow-up demonstrated satisfactory healing of the graft and implant osseointegration. CONCLUSION: Bone ring technique concomitant with Le Fort 1 osteotomy seems to be appropriate to correct jaw discrepancy associated to a single tooth loss of the upper molar region with residual bone height of at least 3 mm to ensure implant primary stability.

Effectiveness of the bone ring technique and simultaneous implant placement for vertical ridge augmentation: a systematic review.

BACKGROUND: Dimensional changes after dental extraction frequently lead to situations in which bone augmentation procedures are required prior to dental implant placement. Bone ring technique (BRT) has been described as a one-stage approach to restore vertical alveolar ridge defects, in which an autogenous or allogeneic cortico-cancellous bone block graft is stabilized with a dental implant inserted simultaneously. The objective of this systematic review was to evaluate the clinical performance of BRT. MATERIALS AND METHODS: This review was conducted according to PRISMA guidelines. An electronic search was conducted in four databases: (1) The National Library of Medicine (MEDLINE/PubMed) via Ovid; (2) Web of Science (WOS); (3) SCOPUS; and (4) Cochrane Central Register of Controlled Trials (CENTRAL). The Newcastle-Ottawa Quality Assessment Scale and The Joanna Briggs Institute Critical Appraisal tool were used to assess the quality of evidence in the studies reviewed. RESULTS: Sixteen studies with a total of 186 patients treated with 219 bone rings bocks were included in the review. The studies showed a mean bone gain of 4.94 mm, mean bone resorption of 0.83 mm, and mean marginal bone loss of 0.57 mm after a mean follow-up period of 13.35 months. A mean bone ring survival rate of 97.26% and implant survival rate of 94.97% were recorded. CONCLUSIONS: BRT would appear to be an adequate alternative technique for restoring single vertical alveolar ridge defects with simultaneous dental implant placement. However, further studies comparing this technique with other vertical ridge augmentation procedures in different clinical scenarios are needed to confirm the present results.

Three-dimensional bone grafting in dental implantology using autogenous bone ring transplant: Clinical outcomes of a one-stage technique.

BACKGROUND: An insufficient bone volume at the maxillary anterior region often restricts dental implant treatment and commonly leads to poor aesthetic outcomes. The defective site requires bone grafting as an initial surgical intervention before dental implant placement. In dental implantology, reconstructing osseous defects using autologous block bone grafts, biomaterials, or a combination of both is a routine surgical procedure. This study aims to evaluate the efficacy of autogenous, symphyseal, bone ring block grafts after the augmentation of defective sockets and clinical application of grafts in the maxillary anterior region with immediate insertion of a dental implant in a single surgical procedure. MATERIALS AND METHODS: The study included eight patients (five females and three males) with 12 defective sockets. The technique included removing the bone from the chin region for transplant, fitting the three-dimensional bone rings in the prepared sockets of the maxillary anterior region, and screwing the dental implants through the rings. Patients underwent postoperative clinical examinations every day during the first week and then every month for 6 months. RESULTS: In two cases, the wound dehisced but healed by secondary intervention during the follow-up period. In one case, the ring graft sequestrated because of infection in postoperative month 2, the osseous defect was reconstructed with biomaterials. The remaining cases healed with no infection, and no other case failed during the first year. CONCLUSION: This technique showed promising and advantageous results, and thus, could be an alternative treatment to other autogenous graft techniques, particularly for defective sockets.

Bone Augmentation and Simultaneous Implant Placement with Allogenic Bone Rings and Analysis of Its Purification Success.

The main objective of this manuscript was to demonstrate the use of freeze-dried bone allografts (FDBA) by means of a technique of simultaneous bone augmentation and implant placement ("Bone Ring Technique") in different indications, i.e., ridge reconstruction and sinus floor elevation procedure with a maxillary bone height of less than 4 mm. Moreover, cases with an up to 3-year follow-up were chosen to analyze the techniques of mid-term clinical success. Finally, the purification success of the FDBA was analyzed by means of established scanning electron microscopic (SEM) and histological methods. The FBDA bone ring was applied in three different patients and indications and presented; the healing success was analyzed on the basis of radiographical and clinical images. For analysis of the purification of the allogeneic bone, previously established histological methods and scanning electron microscopy (SEM) were applied. All analyzed patient cases showed that the FDBA-based bone ring was fully integrated into newly built alveolar bone. Furthermore, the observations revealed that the three-dimensional bone reconstructions in maxilla and mandible were stable within the observational period of up to 3 years. Altogether, the present data show that the application of the Bone Ring Technique using the FDBA rings allows for successful regeneration of alveolar bone with a predictable clinical outcome, functionality and esthetics. Moreover, the material analyses showed that the allogeneic bone tissue was free of cells or cell remnants, while the (ultra-) structure of the bone matrix has been retained. Thus, the biological safety of the FDBA has been confirmed.

[Effects of GBR and Delayed Loading on Bone Ring Grafting with Simultaneous Implant Insertion: an Experimental Study on Beagle Dogs].

OBJECTIVE: To determine the effects of guided bone regeneration (GBR) and delayed loading on autogenous bone ring grafting. METHODS: Autogenous bone ring augmentation with simultaneous implant insertion was performed in the mandibular premolars region of six Beagle dogs. The Bone quality of four mandibular premolars [second premolar (P2) and fourth premolar (P4)] were detected using cone beam CT (CBCT). The P2s and P4s of bilateral mandible were extracted, with three extracting sites being randomly selected to create buccal defects and the remaining one serving as control. GBR and bone ring grafting with simultaneous implant insertion was performed on two of the three experimental sites with buccal defects 3 months later, while the other one was treated with bone ring grafting with simultaneous implant insertion. Routine implant placement was performed in the control group. Vertical bone resorption and sulcus deep around the implants were measured three months after occlusal loading with abutment. RESULTS: Three months after operations, 83.3% of bone rings grafts were successful and 100% of implants survived. Delayed healing appeared more in the dogs with GBR compared those treated with bone ring grafting with simultaneous implant insertion, resulting in an increase in vertical bone resorption. Compared with the control group, delayed loading had no effects on vertical bone resorption and the health of gingiva tissues after autogenous bone ring transplant. CONCLUSION: GBR is not a preferred procedure for bone ring grafts, which may increase the risk of delayed healing and site infections, leading to failure of implants. Healed bone ring grafts can resist loadings as normal.

Vertical bone augmentation in a single-tooth gap with an allogenic bone ring: Clinical considerations.

OBJECTIVE: The main objective of this case report is to introduce a one-stage bone block augmentation with a cylindrical freeze-dried bone allograft (FDBA) and simultaneous implantation for the reconstruction of a single-tooth bone defect. CLINICAL CONSIDERATIONS: The report describes this method on the basis of radiographical and clinical images derived from a single patient. CONCLUSIONS: The report demonstrates the time-saving and successful application of this treatment concept, which has the potential to increase patient satisfaction and comfort. CLINICAL SIGNIFICANCE: The application of the presented technique enabled a prosthetic rehabilitation of the extracted tooth about 3 months earlier as compared to the conventional procedure, while demonstrating no compromises regarding clinical outcome, functionality and esthetics.

Intrasinusal locking technique: a novel use of the ring block technique at sinus perforations for simultaneous implant placement.

Ten patients who underwent sinus lift surgery with simultaneous implant placement using the intrasinusal locking technique were evaluated retrospectively. All patients were scheduled for sinus floor elevation procedures with simultaneous implant placement. Schneiderian membrane perforation occurred during the lifting procedure, and conventional methods failed to repair the perforation. Therefore, an autogenous bone ring was placed at the base of the maxillary sinus and was locked to the alveolar crest with a dental implant. Marginal resorption around the dental implants was measured on panoramic radiographs. Prosthetic rehabilitation was performed at 6 months postoperative. The overall survival rate of the implants over a mean follow-up of 24.3 months was 90%. One case failed due to resorption of the alveolar crest around the implant as a result of infection; the implant and the adjacent ring were removed at 1 month postoperative. At the time of writing, the nine implants placed using the documented technique continue to function well, without any signs of peri-implant disease. The proposed approach allows for simultaneous dental implant placement in the extremely atrophic maxilla, even if there is extensive perforation of the Schneiderian membrane.

Enxerto autógeno Bone Ring e colocação concomitante de implante osseointegrável em região estética ­ relato de caso / Autogenous Bone Ring graft and concomitant placement of osseointegratable implant in an esthetic region ­ case report

A técnica denominada Bone Ring consiste no aumento vertical do rebordo alveolar através de anéis cilíndricos de osso autógeno ou aloplástico, os quais auxiliarão no ganho vertical tridimensional da crista óssea, favorecendo a estética da prótese, o ganho biomecânico, bem como a eliminação de tempo cirúrgico, uma vez que o implante e o enxerto podem ser instalados concomitantemente. O presente estudo apresenta um relato de caso clínico de uma paciente com complicações no canino superior esquerdo. Após insucesso na reabilitação protética com implante osseointegrável, optou-se pelo tratamento com o Bone Ring. A técnica mostrou-se um procedimento seguro e eficiente no caso em questão, otimizando a reabilitação protética funcional e estética (AU).

The Bone Ring technique consists of alveolar ridge vertical increase through cylindrical rings of autogenous or alloplastic bone, which will aid in the three-dimensional vertical gain of the bone crest, favoring prosthesis aesthetics biomechanical gain, as well as the elimination of surgical time, since the implant and the graft can be installed concomitantly. The present study presents a case report of a patient with complications in the upper left canine. After unsuccessful prosthetic rehabilitation with osseointegrable implant, the bone ring treatment was chosen. The technique proved to be a safe and efficient procedure in this case, optimizing functional and aesthetic prosthetic rehabilitation (AU).

Comparative analysis of clinical curative effects of allogeneic bone ring and titanium mesh in repairing adolescent spinal tuberculosis kyphosis / 重庆医学

Objective To compare the clinical curative effect of allogeneic bone ring and titanium mesh in repairing adolescent spinal tuberculosis kyphosis.Methods Forty-four cases of kyphosis after adolescent spinal tuberculosis operation in this hospital from January 2012 to January 2015 were selected as the study subjects and divided into the control group and observation group ac-cording to the treatment types,22 cases in each group.The control group was repaired with titanium mesh,while the observation group was given allogeneic bone ring fusion repair.Postoperative follow up lasted for 2 -5 years.The perioperative indexes,repair material and vertebral fusion and neurological score,preoperative and postoperative Cobb angle,ESR,CRP and postoperative com-plications occurrence were compared between the two groups.Results There was no statistically significant difference in periopera-tive indexes between the two groups(P>0.05).The fusion time,occurrence rate of local pain and motion limitation had statistical differences between the two groups(P<0.05).The occurrence rate of material loosening had no statistical difference(P>0.05). No grade A and B spinal injury appeared in both groups.The incidence rate of grade D and E in the observation group was signifi-cantly lower than that in the control group,the difference was statistically significant(P<0.05).The postoperative Cobb angle, ESR and CRP had no statistical difference between the two groups(P>0.05),moreover no significant adverse reactions and post-operative tuberculosis recurrence occurred.Conclusion Allogeneic bone ring and titanium mesh have satisfactory effect for repairing juvenile spinal tuberculosis kyphosis,allogeneic bone ring fusion time is longer,early stability is worse than the titanium mesh,the brace protection is needed in the early time,but the clinical effect of patients is more significant,which is worthy of being promoted and applied in clinical treatment.

Bone Ring Augmentation Around Immediate Implants: A Clinical and Radiographic Study.

PURPOSE: The purpose of this study was to evaluate the efficacy of bone ring augmentation technique for three-dimensional augmentation of severely defective sockets along with placement of immediate dental implants. MATERIALS AND METHODS: A clinical study was conducted on 14 patients with 15 defective sockets requiring extractions and immediate implant placement. Following extraction, bone ring with an implant osteotomy, harvested from chin, was sculptured and fitted into the extraction socket. The bone apical to the socket was prepared for implant through the central osteotomy of the ring. Implant was then placed through the ring into the apical bone. After 6 months, prosthesis was placed. Clinical and radiographic examination was done to evaluate the soft tissue and crestal bone level around implants immediate postoperatively and at 1st, 3rd, 6th, and 9th month postoperatively. RESULTS: Out of 15 grafted sockets, 14 showed an evidence of bone healing with no significant crestal bone resorption. One ring showed soft tissue dehiscence which underwent severe resorption at 6th month postoperative visit. CONCLUSION: The bone ring augmentation technique is an effective method for three-dimensional augmentation of severely defective sockets. This technique helps in reducing the overall treatment time by allowing grafting and placement of implant simultaneously in a single visit. However, longer observation periods are needed to draw more definite conclusions on the success of bone ring augmentation technique.

Aumento ósseo vertical com instalação simultânea de implante dentário pela técnica Bone Ring ­ acompanhamento clínico de dois anos / Vertical bone augmentation with simultaneous placement of dental implant using the bone ring technique ­ a 2-year clinical follow-up

Os procedimentos de enxertia óssea para ganho vertical ainda são temerários na Implantodontia. Não há um consenso na literatura sobre as técnicas para aumento em altura da crista óssea alveolar para futura colocação de implantes. Além disso, o tempo de tratamento é demasiadamente prolongado quando são realizadas as técnicas de enxerto ósseo com implantação tardia. Sendo assim, o objetivo deste trabalho foi descrever uma técnica para aumento ósseo vertical simultâneo à instalação de implante denominado bone ring. Paciente apresentando severo defeito ósseo em altura e largura na região do dente 14 foi reabilitada a partir da reconstrução óssea tridimensional com anel ósseo removido da área mentual e implantação imediata à fixação do enxerto. Após seis meses, foram realizados a reabertura e procedimentos protéticos de personalização de perfil de emergência, com posterior instalação de coroa metalocerâmica. Decorridos dois anos de acompanhamento, notou-se estabilidade tecidual peri-implantar sem remodelações severas do tecido ósseo peri-implantar. Pôde-se concluir que a técnica de reconstrução óssea tridimensional simultânea à instalação de implante ­ bone ring ­ é uma alternativa viável, mediante rigoroso planejamento e curva de aprendizado indicada para defeitos ósseos severos.

Bone grafting procedures for vertical bone augmentation are still an issue on implant dentistry. There is no literature consensus regarding techniques for alveolar ridge height increase for further implant placement. Besides, treatment times are extended in case of delayed implant placement. The aim of this paper was to describe a technique for vertical bone augmentation at the same time of implant installation (bone ring). A patient having a several bone defect in height and width at the region of tooth 14 received a 3D reconstruction with a bone ring removed from the chin area. Six months later, implant exposure was performed with procedures for soft tissue conditioning and delivery of a metalloceramic restoration. Tissue stability and no significant bone remodeling were observed after two years. The proposed technique for three-dimensional reconstruction ­ bone ring ­ is a viable alternative provided that judicious treatment planning and considerable learning curve are observed to manage severe bone defects.